1. Field
Exemplary embodiments of the present disclosure relate to data transmission and reception technology between terminals.
2. Discussion of Related Art
When two terminals transmit and receive data between each other over a network, each terminal splits the data to be transmitted into a plurality of pieces and transmits the split data to the other terminal. However, since the network environment for connecting the terminals changes in real time, messages may arrive out of order or some of the messages may be lost. Further, a replay attack may occur when a malicious third party on the network intercepts data and transmits the data several times to a reception terminal.
To solve the problem, each terminal transmits pieces of data after assigning serial numbers to the respective pieces of data to specify the processing order of the transmitted data. Accordingly, the reception terminal is configured to determine the order of each received message according to the serial number of the message or determine whether the message has already been received. However, such a conventional scheme for transmitting messages involves simply discarding a message that has a serial number smaller than that of a lastly received message and unconditionally receiving a message that has a serial number greater than the lastly received message. Accordingly, the conventional message transmission scheme suffers from an unnecessarily high message retransmission ratio, and has a limited capability of protecting against replay attacks.